What drives herbivory patterns in a sugar maple forest?
– Dr. Emma Despland, Mahsa Hakimara (PhD), Colette Ethier (Concordia), Isabel Fournier (McGill)
Insect herbivores have long been recognized as important drivers of forest ecosystems by damaging leaves, weakening, or even killing trees and decreasing forest productivity. Sugar maple (Acer saccharum) forests in Quebec are declining. First, this project will evaluate the extent to which herbivores may contribute to this decline and second to document insect biodiversity supported by maples that could be threatened by this decline. The distribution of herbivorous insects in forests is expected to vary due to different biotic and abiotic factors associated with forest structure. One important but poorly studied aspect of structural diversity of temperate forests is the vertical gradient which provides several microhabitats with different levels of light, temperature, humidity, leaf quality and predator activity. Therefore, the objectives of this project are: 1) determine if vertical stratification effects herbivory, 2) understand how this stratification effect varies between different herbivore guilds and 3) show how this vertical stratification affects bottom-up (plant traits as the herbivore host) and top-down (predators and parasitoids) trophic relationships that shape herbivory patterns in a tree. The methods include assessing environmental factors, herbivory damage and leaf quality in three strata (sun canopy, shade canopy, and understory) of 12 sugar maple trees.
Stay tuned for results